ThinkReservations was built with redundancy in mind. Your data is stored on our database which has an up-to-the-moment back up copy that exists in a completely different data center.
We have systems in place to automatically "fail over" to the back up copy if the original database server has any issue. Every night, the entire data set (including your data!) is backed up and stored with 99.999999999% durability - that's nine 9s! Even the back ups are stored across multiple data centers and time zones to make sure they are always available.
Suffice to say, your data is very safe!